California's attorney general is suing the Trump administration for rolling back a fracking rule that he says is designed to protect public health and the environment.
Attorney General Xavier Becerra announced the lawsuit as he celebrated his first year as California's top law enforcement official.
He says his office has filed 25 lawsuits against President Donald Trump's administration.
"We take this action to protect the 40 million people of our great state of California against federal overreach and to insist that the rule of law be followed by everyone, including the occupant in the White House," Becerra said.
The latest suit challenges the federal Bureau of Land Management's rollback of a major rule last month governing fracking, which cracks open underground oil and gas deposits with pressurized water, sand and chemicals. The rule would require drilling companies to disclose the chemicals they use for fracking.